1 /* SPDX-License-Identifier: GPL-2.0 */
2 /*
3 * Written by Mark Hemment, 1996 (markhe@nextd.demon.co.uk).
4 *
5 * (C) SGI 2006, Christoph Lameter
6 * Cleaned up and restructured to ease the addition of alternative
7 * implementations of SLAB allocators.
8 * (C) Linux Foundation 2008-2013
9 * Unified interface for all slab allocators
10 */
11
12 #ifndef _LINUX_SLAB_H
13 #define _LINUX_SLAB_H
14
15 #include <linux/cache.h>
16 #include <linux/gfp.h>
17 #include <linux/overflow.h>
18 #include <linux/types.h>
19 #include <linux/workqueue.h>
20 #include <linux/percpu-refcount.h>
21 #include <linux/cleanup.h>
22 #include <linux/hash.h>
23
24 enum _slab_flag_bits {
25 _SLAB_CONSISTENCY_CHECKS,
26 _SLAB_RED_ZONE,
27 _SLAB_POISON,
28 _SLAB_KMALLOC,
29 _SLAB_HWCACHE_ALIGN,
30 _SLAB_CACHE_DMA,
31 _SLAB_CACHE_DMA32,
32 _SLAB_STORE_USER,
33 _SLAB_PANIC,
34 _SLAB_TYPESAFE_BY_RCU,
35 _SLAB_TRACE,
36 #ifdef CONFIG_DEBUG_OBJECTS
37 _SLAB_DEBUG_OBJECTS,
38 #endif
39 _SLAB_NOLEAKTRACE,
40 _SLAB_NO_MERGE,
41 #ifdef CONFIG_FAILSLAB
42 _SLAB_FAILSLAB,
43 #endif
44 #ifdef CONFIG_MEMCG
45 _SLAB_ACCOUNT,
46 #endif
47 #ifdef CONFIG_KASAN_GENERIC
48 _SLAB_KASAN,
49 #endif
50 _SLAB_NO_USER_FLAGS,
51 #ifdef CONFIG_KFENCE
52 _SLAB_SKIP_KFENCE,
53 #endif
54 #ifndef CONFIG_SLUB_TINY
55 _SLAB_RECLAIM_ACCOUNT,
56 #endif
57 _SLAB_OBJECT_POISON,
58 _SLAB_CMPXCHG_DOUBLE,
59 #ifdef CONFIG_SLAB_OBJ_EXT
60 _SLAB_NO_OBJ_EXT,
61 #endif
62 _SLAB_FLAGS_LAST_BIT
63 };
64
65 #define __SLAB_FLAG_BIT(nr) ((slab_flags_t __force)(1U << (nr)))
66 #define __SLAB_FLAG_UNUSED ((slab_flags_t __force)(0U))
67
68 /*
69 * Flags to pass to kmem_cache_create().
70 * The ones marked DEBUG need CONFIG_SLUB_DEBUG enabled, otherwise are no-op
71 */
72 /* DEBUG: Perform (expensive) checks on alloc/free */
73 #define SLAB_CONSISTENCY_CHECKS __SLAB_FLAG_BIT(_SLAB_CONSISTENCY_CHECKS)
74 /* DEBUG: Red zone objs in a cache */
75 #define SLAB_RED_ZONE __SLAB_FLAG_BIT(_SLAB_RED_ZONE)
76 /* DEBUG: Poison objects */
77 #define SLAB_POISON __SLAB_FLAG_BIT(_SLAB_POISON)
78 /* Indicate a kmalloc slab */
79 #define SLAB_KMALLOC __SLAB_FLAG_BIT(_SLAB_KMALLOC)
80 /* Align objs on cache lines */
81 #define SLAB_HWCACHE_ALIGN __SLAB_FLAG_BIT(_SLAB_HWCACHE_ALIGN)
82 /* Use GFP_DMA memory */
83 #define SLAB_CACHE_DMA __SLAB_FLAG_BIT(_SLAB_CACHE_DMA)
84 /* Use GFP_DMA32 memory */
85 #define SLAB_CACHE_DMA32 __SLAB_FLAG_BIT(_SLAB_CACHE_DMA32)
86 /* DEBUG: Store the last owner for bug hunting */
87 #define SLAB_STORE_USER __SLAB_FLAG_BIT(_SLAB_STORE_USER)
88 /* Panic if kmem_cache_create() fails */
89 #define SLAB_PANIC __SLAB_FLAG_BIT(_SLAB_PANIC)
90 /*
91 * SLAB_TYPESAFE_BY_RCU - **WARNING** READ THIS!
92 *
93 * This delays freeing the SLAB page by a grace period, it does _NOT_
94 * delay object freeing. This means that if you do kmem_cache_free()
95 * that memory location is free to be reused at any time. Thus it may
96 * be possible to see another object there in the same RCU grace period.
97 *
98 * This feature only ensures the memory location backing the object
99 * stays valid, the trick to using this is relying on an independent
100 * object validation pass. Something like:
101 *
102 * begin:
103 * rcu_read_lock();
104 * obj = lockless_lookup(key);
105 * if (obj) {
106 * if (!try_get_ref(obj)) // might fail for free objects
107 * rcu_read_unlock();
108 * goto begin;
109 *
110 * if (obj->key != key) { // not the object we expected
111 * put_ref(obj);
112 * rcu_read_unlock();
113 * goto begin;
114 * }
115 * }
116 * rcu_read_unlock();
117 *
118 * This is useful if we need to approach a kernel structure obliquely,
119 * from its address obtained without the usual locking. We can lock
120 * the structure to stabilize it and check it's still at the given address,
121 * only if we can be sure that the memory has not been meanwhile reused
122 * for some other kind of object (which our subsystem's lock might corrupt).
123 *
124 * rcu_read_lock before reading the address, then rcu_read_unlock after
125 * taking the spinlock within the structure expected at that address.
126 *
127 * Note that object identity check has to be done *after* acquiring a
128 * reference, therefore user has to ensure proper ordering for loads.
129 * Similarly, when initializing objects allocated with SLAB_TYPESAFE_BY_RCU,
130 * the newly allocated object has to be fully initialized *before* its
131 * refcount gets initialized and proper ordering for stores is required.
132 * refcount_{add|inc}_not_zero_acquire() and refcount_set_release() are
133 * designed with the proper fences required for reference counting objects
134 * allocated with SLAB_TYPESAFE_BY_RCU.
135 *
136 * Note that it is not possible to acquire a lock within a structure
137 * allocated with SLAB_TYPESAFE_BY_RCU without first acquiring a reference
138 * as described above. The reason is that SLAB_TYPESAFE_BY_RCU pages
139 * are not zeroed before being given to the slab, which means that any
140 * locks must be initialized after each and every kmem_struct_alloc().
141 * Alternatively, make the ctor passed to kmem_cache_create() initialize
142 * the locks at page-allocation time, as is done in __i915_request_ctor(),
143 * sighand_ctor(), and anon_vma_ctor(). Such a ctor permits readers
144 * to safely acquire those ctor-initialized locks under rcu_read_lock()
145 * protection.
146 *
147 * Note that SLAB_TYPESAFE_BY_RCU was originally named SLAB_DESTROY_BY_RCU.
148 */
149 /* Defer freeing slabs to RCU */
150 #define SLAB_TYPESAFE_BY_RCU __SLAB_FLAG_BIT(_SLAB_TYPESAFE_BY_RCU)
151 /* Trace allocations and frees */
152 #define SLAB_TRACE __SLAB_FLAG_BIT(_SLAB_TRACE)
153
154 /* Flag to prevent checks on free */
155 #ifdef CONFIG_DEBUG_OBJECTS
156 # define SLAB_DEBUG_OBJECTS __SLAB_FLAG_BIT(_SLAB_DEBUG_OBJECTS)
157 #else
158 # define SLAB_DEBUG_OBJECTS __SLAB_FLAG_UNUSED
159 #endif
160
161 /* Avoid kmemleak tracing */
162 #define SLAB_NOLEAKTRACE __SLAB_FLAG_BIT(_SLAB_NOLEAKTRACE)
163
164 /*
165 * Prevent merging with compatible kmem caches. This flag should be used
166 * cautiously. Valid use cases:
167 *
168 * - caches created for self-tests (e.g. kunit)
169 * - general caches created and used by a subsystem, only when a
170 * (subsystem-specific) debug option is enabled
171 * - performance critical caches, should be very rare and consulted with slab
172 * maintainers, and not used together with CONFIG_SLUB_TINY
173 */
174 #define SLAB_NO_MERGE __SLAB_FLAG_BIT(_SLAB_NO_MERGE)
175
176 /* Fault injection mark */
177 #ifdef CONFIG_FAILSLAB
178 # define SLAB_FAILSLAB __SLAB_FLAG_BIT(_SLAB_FAILSLAB)
179 #else
180 # define SLAB_FAILSLAB __SLAB_FLAG_UNUSED
181 #endif
182 /* Account to memcg */
183 #ifdef CONFIG_MEMCG
184 # define SLAB_ACCOUNT __SLAB_FLAG_BIT(_SLAB_ACCOUNT)
185 #else
186 # define SLAB_ACCOUNT __SLAB_FLAG_UNUSED
187 #endif
188
189 #ifdef CONFIG_KASAN_GENERIC
190 #define SLAB_KASAN __SLAB_FLAG_BIT(_SLAB_KASAN)
191 #else
192 #define SLAB_KASAN __SLAB_FLAG_UNUSED
193 #endif
194
195 /*
196 * Ignore user specified debugging flags.
197 * Intended for caches created for self-tests so they have only flags
198 * specified in the code and other flags are ignored.
199 */
200 #define SLAB_NO_USER_FLAGS __SLAB_FLAG_BIT(_SLAB_NO_USER_FLAGS)
201
202 #ifdef CONFIG_KFENCE
203 #define SLAB_SKIP_KFENCE __SLAB_FLAG_BIT(_SLAB_SKIP_KFENCE)
204 #else
205 #define SLAB_SKIP_KFENCE __SLAB_FLAG_UNUSED
206 #endif
207
208 /* The following flags affect the page allocator grouping pages by mobility */
209 /* Objects are reclaimable */
210 #ifndef CONFIG_SLUB_TINY
211 #define SLAB_RECLAIM_ACCOUNT __SLAB_FLAG_BIT(_SLAB_RECLAIM_ACCOUNT)
212 #else
213 #define SLAB_RECLAIM_ACCOUNT __SLAB_FLAG_UNUSED
214 #endif
215 #define SLAB_TEMPORARY SLAB_RECLAIM_ACCOUNT /* Objects are short-lived */
216
217 /* Slab created using create_boot_cache */
218 #ifdef CONFIG_SLAB_OBJ_EXT
219 #define SLAB_NO_OBJ_EXT __SLAB_FLAG_BIT(_SLAB_NO_OBJ_EXT)
220 #else
221 #define SLAB_NO_OBJ_EXT __SLAB_FLAG_UNUSED
222 #endif
223
224 /*
225 * ZERO_SIZE_PTR will be returned for zero sized kmalloc requests.
226 *
227 * Dereferencing ZERO_SIZE_PTR will lead to a distinct access fault.
228 *
229 * ZERO_SIZE_PTR can be passed to kfree though in the same way that NULL can.
230 * Both make kfree a no-op.
231 */
232 #define ZERO_SIZE_PTR ((void *)16)
233
234 #define ZERO_OR_NULL_PTR(x) ((unsigned long)(x) <= \
235 (unsigned long)ZERO_SIZE_PTR)
236
237 #include <linux/kasan.h>
238
239 struct list_lru;
240 struct mem_cgroup;
241 /*
242 * struct kmem_cache related prototypes
243 */
244 bool slab_is_available(void);
245
246 /**
247 * struct kmem_cache_args - Less common arguments for kmem_cache_create()
248 *
249 * Any uninitialized fields of the structure are interpreted as unused. The
250 * exception is @freeptr_offset where %0 is a valid value, so
251 * @use_freeptr_offset must be also set to %true in order to interpret the field
252 * as used. For @useroffset %0 is also valid, but only with non-%0
253 * @usersize.
254 *
255 * When %NULL args is passed to kmem_cache_create(), it is equivalent to all
256 * fields unused.
257 */
258 struct kmem_cache_args {
259 /**
260 * @align: The required alignment for the objects.
261 *
262 * %0 means no specific alignment is requested.
263 */
264 unsigned int align;
265 /**
266 * @useroffset: Usercopy region offset.
267 *
268 * %0 is a valid offset, when @usersize is non-%0
269 */
270 unsigned int useroffset;
271 /**
272 * @usersize: Usercopy region size.
273 *
274 * %0 means no usercopy region is specified.
275 */
276 unsigned int usersize;
277 /**
278 * @freeptr_offset: Custom offset for the free pointer
279 * in &SLAB_TYPESAFE_BY_RCU caches
280 *
281 * By default &SLAB_TYPESAFE_BY_RCU caches place the free pointer
282 * outside of the object. This might cause the object to grow in size.
283 * Cache creators that have a reason to avoid this can specify a custom
284 * free pointer offset in their struct where the free pointer will be
285 * placed.
286 *
287 * Note that placing the free pointer inside the object requires the
288 * caller to ensure that no fields are invalidated that are required to
289 * guard against object recycling (See &SLAB_TYPESAFE_BY_RCU for
290 * details).
291 *
292 * Using %0 as a value for @freeptr_offset is valid. If @freeptr_offset
293 * is specified, %use_freeptr_offset must be set %true.
294 *
295 * Note that @ctor currently isn't supported with custom free pointers
296 * as a @ctor requires an external free pointer.
297 */
298 unsigned int freeptr_offset;
299 /**
300 * @use_freeptr_offset: Whether a @freeptr_offset is used.
301 */
302 bool use_freeptr_offset;
303 /**
304 * @ctor: A constructor for the objects.
305 *
306 * The constructor is invoked for each object in a newly allocated slab
307 * page. It is the cache user's responsibility to free object in the
308 * same state as after calling the constructor, or deal appropriately
309 * with any differences between a freshly constructed and a reallocated
310 * object.
311 *
312 * %NULL means no constructor.
313 */
314 void (*ctor)(void *);
315 };
316
317 struct kmem_cache *__kmem_cache_create_args(const char *name,
318 unsigned int object_size,
319 struct kmem_cache_args *args,
320 slab_flags_t flags);
321 static inline struct kmem_cache *
__kmem_cache_create(const char * name,unsigned int size,unsigned int align,slab_flags_t flags,void (* ctor)(void *))322 __kmem_cache_create(const char *name, unsigned int size, unsigned int align,
323 slab_flags_t flags, void (*ctor)(void *))
324 {
325 struct kmem_cache_args kmem_args = {
326 .align = align,
327 .ctor = ctor,
328 };
329
330 return __kmem_cache_create_args(name, size, &kmem_args, flags);
331 }
332
333 /**
334 * kmem_cache_create_usercopy - Create a kmem cache with a region suitable
335 * for copying to userspace.
336 * @name: A string which is used in /proc/slabinfo to identify this cache.
337 * @size: The size of objects to be created in this cache.
338 * @align: The required alignment for the objects.
339 * @flags: SLAB flags
340 * @useroffset: Usercopy region offset
341 * @usersize: Usercopy region size
342 * @ctor: A constructor for the objects, or %NULL.
343 *
344 * This is a legacy wrapper, new code should use either KMEM_CACHE_USERCOPY()
345 * if whitelisting a single field is sufficient, or kmem_cache_create() with
346 * the necessary parameters passed via the args parameter (see
347 * &struct kmem_cache_args)
348 *
349 * Return: a pointer to the cache on success, NULL on failure.
350 */
351 static inline struct kmem_cache *
kmem_cache_create_usercopy(const char * name,unsigned int size,unsigned int align,slab_flags_t flags,unsigned int useroffset,unsigned int usersize,void (* ctor)(void *))352 kmem_cache_create_usercopy(const char *name, unsigned int size,
353 unsigned int align, slab_flags_t flags,
354 unsigned int useroffset, unsigned int usersize,
355 void (*ctor)(void *))
356 {
357 struct kmem_cache_args kmem_args = {
358 .align = align,
359 .ctor = ctor,
360 .useroffset = useroffset,
361 .usersize = usersize,
362 };
363
364 return __kmem_cache_create_args(name, size, &kmem_args, flags);
365 }
366
367 /* If NULL is passed for @args, use this variant with default arguments. */
368 static inline struct kmem_cache *
__kmem_cache_default_args(const char * name,unsigned int size,struct kmem_cache_args * args,slab_flags_t flags)369 __kmem_cache_default_args(const char *name, unsigned int size,
370 struct kmem_cache_args *args,
371 slab_flags_t flags)
372 {
373 struct kmem_cache_args kmem_default_args = {};
374
375 /* Make sure we don't get passed garbage. */
376 if (WARN_ON_ONCE(args))
377 return ERR_PTR(-EINVAL);
378
379 return __kmem_cache_create_args(name, size, &kmem_default_args, flags);
380 }
381
382 /**
383 * kmem_cache_create - Create a kmem cache.
384 * @__name: A string which is used in /proc/slabinfo to identify this cache.
385 * @__object_size: The size of objects to be created in this cache.
386 * @__args: Optional arguments, see &struct kmem_cache_args. Passing %NULL
387 * means defaults will be used for all the arguments.
388 *
389 * This is currently implemented as a macro using ``_Generic()`` to call
390 * either the new variant of the function, or a legacy one.
391 *
392 * The new variant has 4 parameters:
393 * ``kmem_cache_create(name, object_size, args, flags)``
394 *
395 * See __kmem_cache_create_args() which implements this.
396 *
397 * The legacy variant has 5 parameters:
398 * ``kmem_cache_create(name, object_size, align, flags, ctor)``
399 *
400 * The align and ctor parameters map to the respective fields of
401 * &struct kmem_cache_args
402 *
403 * Context: Cannot be called within a interrupt, but can be interrupted.
404 *
405 * Return: a pointer to the cache on success, NULL on failure.
406 */
407 #define kmem_cache_create(__name, __object_size, __args, ...) \
408 _Generic((__args), \
409 struct kmem_cache_args *: __kmem_cache_create_args, \
410 void *: __kmem_cache_default_args, \
411 default: __kmem_cache_create)(__name, __object_size, __args, __VA_ARGS__)
412
413 void kmem_cache_destroy(struct kmem_cache *s);
414 int kmem_cache_shrink(struct kmem_cache *s);
415
416 /*
417 * Please use this macro to create slab caches. Simply specify the
418 * name of the structure and maybe some flags that are listed above.
419 *
420 * The alignment of the struct determines object alignment. If you
421 * f.e. add ____cacheline_aligned_in_smp to the struct declaration
422 * then the objects will be properly aligned in SMP configurations.
423 */
424 #define KMEM_CACHE(__struct, __flags) \
425 __kmem_cache_create_args(#__struct, sizeof(struct __struct), \
426 &(struct kmem_cache_args) { \
427 .align = __alignof__(struct __struct), \
428 }, (__flags))
429
430 /*
431 * To whitelist a single field for copying to/from usercopy, use this
432 * macro instead for KMEM_CACHE() above.
433 */
434 #define KMEM_CACHE_USERCOPY(__struct, __flags, __field) \
435 __kmem_cache_create_args(#__struct, sizeof(struct __struct), \
436 &(struct kmem_cache_args) { \
437 .align = __alignof__(struct __struct), \
438 .useroffset = offsetof(struct __struct, __field), \
439 .usersize = sizeof_field(struct __struct, __field), \
440 }, (__flags))
441
442 /*
443 * Common kmalloc functions provided by all allocators
444 */
445 void * __must_check krealloc_noprof(const void *objp, size_t new_size,
446 gfp_t flags) __realloc_size(2);
447 #define krealloc(...) alloc_hooks(krealloc_noprof(__VA_ARGS__))
448
449 void kfree(const void *objp);
450 void kfree_sensitive(const void *objp);
451 size_t __ksize(const void *objp);
452
453 DEFINE_FREE(kfree, void *, if (!IS_ERR_OR_NULL(_T)) kfree(_T))
454
455 /**
456 * ksize - Report actual allocation size of associated object
457 *
458 * @objp: Pointer returned from a prior kmalloc()-family allocation.
459 *
460 * This should not be used for writing beyond the originally requested
461 * allocation size. Either use krealloc() or round up the allocation size
462 * with kmalloc_size_roundup() prior to allocation. If this is used to
463 * access beyond the originally requested allocation size, UBSAN_BOUNDS
464 * and/or FORTIFY_SOURCE may trip, since they only know about the
465 * originally allocated size via the __alloc_size attribute.
466 */
467 size_t ksize(const void *objp);
468
469 #ifdef CONFIG_PRINTK
470 bool kmem_dump_obj(void *object);
471 #else
kmem_dump_obj(void * object)472 static inline bool kmem_dump_obj(void *object) { return false; }
473 #endif
474
475 /*
476 * Some archs want to perform DMA into kmalloc caches and need a guaranteed
477 * alignment larger than the alignment of a 64-bit integer.
478 * Setting ARCH_DMA_MINALIGN in arch headers allows that.
479 */
480 #ifdef ARCH_HAS_DMA_MINALIGN
481 #if ARCH_DMA_MINALIGN > 8 && !defined(ARCH_KMALLOC_MINALIGN)
482 #define ARCH_KMALLOC_MINALIGN ARCH_DMA_MINALIGN
483 #endif
484 #endif
485
486 #ifndef ARCH_KMALLOC_MINALIGN
487 #define ARCH_KMALLOC_MINALIGN __alignof__(unsigned long long)
488 #elif ARCH_KMALLOC_MINALIGN > 8
489 #define KMALLOC_MIN_SIZE ARCH_KMALLOC_MINALIGN
490 #define KMALLOC_SHIFT_LOW ilog2(KMALLOC_MIN_SIZE)
491 #endif
492
493 /*
494 * Setting ARCH_SLAB_MINALIGN in arch headers allows a different alignment.
495 * Intended for arches that get misalignment faults even for 64 bit integer
496 * aligned buffers.
497 */
498 #ifndef ARCH_SLAB_MINALIGN
499 #define ARCH_SLAB_MINALIGN __alignof__(unsigned long long)
500 #endif
501
502 /*
503 * Arches can define this function if they want to decide the minimum slab
504 * alignment at runtime. The value returned by the function must be a power
505 * of two and >= ARCH_SLAB_MINALIGN.
506 */
507 #ifndef arch_slab_minalign
arch_slab_minalign(void)508 static inline unsigned int arch_slab_minalign(void)
509 {
510 return ARCH_SLAB_MINALIGN;
511 }
512 #endif
513
514 /*
515 * kmem_cache_alloc and friends return pointers aligned to ARCH_SLAB_MINALIGN.
516 * kmalloc and friends return pointers aligned to both ARCH_KMALLOC_MINALIGN
517 * and ARCH_SLAB_MINALIGN, but here we only assume the former alignment.
518 */
519 #define __assume_kmalloc_alignment __assume_aligned(ARCH_KMALLOC_MINALIGN)
520 #define __assume_slab_alignment __assume_aligned(ARCH_SLAB_MINALIGN)
521 #define __assume_page_alignment __assume_aligned(PAGE_SIZE)
522
523 /*
524 * Kmalloc array related definitions
525 */
526
527 /*
528 * SLUB directly allocates requests fitting in to an order-1 page
529 * (PAGE_SIZE*2). Larger requests are passed to the page allocator.
530 */
531 #define KMALLOC_SHIFT_HIGH (PAGE_SHIFT + 1)
532 #define KMALLOC_SHIFT_MAX (MAX_PAGE_ORDER + PAGE_SHIFT)
533 #ifndef KMALLOC_SHIFT_LOW
534 #define KMALLOC_SHIFT_LOW 3
535 #endif
536
537 /* Maximum allocatable size */
538 #define KMALLOC_MAX_SIZE (1UL << KMALLOC_SHIFT_MAX)
539 /* Maximum size for which we actually use a slab cache */
540 #define KMALLOC_MAX_CACHE_SIZE (1UL << KMALLOC_SHIFT_HIGH)
541 /* Maximum order allocatable via the slab allocator */
542 #define KMALLOC_MAX_ORDER (KMALLOC_SHIFT_MAX - PAGE_SHIFT)
543
544 /*
545 * Kmalloc subsystem.
546 */
547 #ifndef KMALLOC_MIN_SIZE
548 #define KMALLOC_MIN_SIZE (1 << KMALLOC_SHIFT_LOW)
549 #endif
550
551 /*
552 * This restriction comes from byte sized index implementation.
553 * Page size is normally 2^12 bytes and, in this case, if we want to use
554 * byte sized index which can represent 2^8 entries, the size of the object
555 * should be equal or greater to 2^12 / 2^8 = 2^4 = 16.
556 * If minimum size of kmalloc is less than 16, we use it as minimum object
557 * size and give up to use byte sized index.
558 */
559 #define SLAB_OBJ_MIN_SIZE (KMALLOC_MIN_SIZE < 16 ? \
560 (KMALLOC_MIN_SIZE) : 16)
561
562 #ifdef CONFIG_RANDOM_KMALLOC_CACHES
563 #define RANDOM_KMALLOC_CACHES_NR 15 // # of cache copies
564 #else
565 #define RANDOM_KMALLOC_CACHES_NR 0
566 #endif
567
568 /*
569 * Whenever changing this, take care of that kmalloc_type() and
570 * create_kmalloc_caches() still work as intended.
571 *
572 * KMALLOC_NORMAL can contain only unaccounted objects whereas KMALLOC_CGROUP
573 * is for accounted but unreclaimable and non-dma objects. All the other
574 * kmem caches can have both accounted and unaccounted objects.
575 */
576 enum kmalloc_cache_type {
577 KMALLOC_NORMAL = 0,
578 #ifndef CONFIG_ZONE_DMA
579 KMALLOC_DMA = KMALLOC_NORMAL,
580 #endif
581 #ifndef CONFIG_MEMCG
582 KMALLOC_CGROUP = KMALLOC_NORMAL,
583 #endif
584 KMALLOC_RANDOM_START = KMALLOC_NORMAL,
585 KMALLOC_RANDOM_END = KMALLOC_RANDOM_START + RANDOM_KMALLOC_CACHES_NR,
586 #ifdef CONFIG_SLUB_TINY
587 KMALLOC_RECLAIM = KMALLOC_NORMAL,
588 #else
589 KMALLOC_RECLAIM,
590 #endif
591 #ifdef CONFIG_ZONE_DMA
592 KMALLOC_DMA,
593 #endif
594 #ifdef CONFIG_MEMCG
595 KMALLOC_CGROUP,
596 #endif
597 NR_KMALLOC_TYPES
598 };
599
600 typedef struct kmem_cache * kmem_buckets[KMALLOC_SHIFT_HIGH + 1];
601
602 extern kmem_buckets kmalloc_caches[NR_KMALLOC_TYPES];
603
604 /*
605 * Define gfp bits that should not be set for KMALLOC_NORMAL.
606 */
607 #define KMALLOC_NOT_NORMAL_BITS \
608 (__GFP_RECLAIMABLE | \
609 (IS_ENABLED(CONFIG_ZONE_DMA) ? __GFP_DMA : 0) | \
610 (IS_ENABLED(CONFIG_MEMCG) ? __GFP_ACCOUNT : 0))
611
612 extern unsigned long random_kmalloc_seed;
613
kmalloc_type(gfp_t flags,unsigned long caller)614 static __always_inline enum kmalloc_cache_type kmalloc_type(gfp_t flags, unsigned long caller)
615 {
616 /*
617 * The most common case is KMALLOC_NORMAL, so test for it
618 * with a single branch for all the relevant flags.
619 */
620 if (likely((flags & KMALLOC_NOT_NORMAL_BITS) == 0))
621 #ifdef CONFIG_RANDOM_KMALLOC_CACHES
622 /* RANDOM_KMALLOC_CACHES_NR (=15) copies + the KMALLOC_NORMAL */
623 return KMALLOC_RANDOM_START + hash_64(caller ^ random_kmalloc_seed,
624 ilog2(RANDOM_KMALLOC_CACHES_NR + 1));
625 #else
626 return KMALLOC_NORMAL;
627 #endif
628
629 /*
630 * At least one of the flags has to be set. Their priorities in
631 * decreasing order are:
632 * 1) __GFP_DMA
633 * 2) __GFP_RECLAIMABLE
634 * 3) __GFP_ACCOUNT
635 */
636 if (IS_ENABLED(CONFIG_ZONE_DMA) && (flags & __GFP_DMA))
637 return KMALLOC_DMA;
638 if (!IS_ENABLED(CONFIG_MEMCG) || (flags & __GFP_RECLAIMABLE))
639 return KMALLOC_RECLAIM;
640 else
641 return KMALLOC_CGROUP;
642 }
643
644 /*
645 * Figure out which kmalloc slab an allocation of a certain size
646 * belongs to.
647 * 0 = zero alloc
648 * 1 = 65 .. 96 bytes
649 * 2 = 129 .. 192 bytes
650 * n = 2^(n-1)+1 .. 2^n
651 *
652 * Note: __kmalloc_index() is compile-time optimized, and not runtime optimized;
653 * typical usage is via kmalloc_index() and therefore evaluated at compile-time.
654 * Callers where !size_is_constant should only be test modules, where runtime
655 * overheads of __kmalloc_index() can be tolerated. Also see kmalloc_slab().
656 */
__kmalloc_index(size_t size,bool size_is_constant)657 static __always_inline unsigned int __kmalloc_index(size_t size,
658 bool size_is_constant)
659 {
660 if (!size)
661 return 0;
662
663 if (size <= KMALLOC_MIN_SIZE)
664 return KMALLOC_SHIFT_LOW;
665
666 if (KMALLOC_MIN_SIZE <= 32 && size > 64 && size <= 96)
667 return 1;
668 if (KMALLOC_MIN_SIZE <= 64 && size > 128 && size <= 192)
669 return 2;
670 if (size <= 8) return 3;
671 if (size <= 16) return 4;
672 if (size <= 32) return 5;
673 if (size <= 64) return 6;
674 if (size <= 128) return 7;
675 if (size <= 256) return 8;
676 if (size <= 512) return 9;
677 if (size <= 1024) return 10;
678 if (size <= 2 * 1024) return 11;
679 if (size <= 4 * 1024) return 12;
680 if (size <= 8 * 1024) return 13;
681 if (size <= 16 * 1024) return 14;
682 if (size <= 32 * 1024) return 15;
683 if (size <= 64 * 1024) return 16;
684 if (size <= 128 * 1024) return 17;
685 if (size <= 256 * 1024) return 18;
686 if (size <= 512 * 1024) return 19;
687 if (size <= 1024 * 1024) return 20;
688 if (size <= 2 * 1024 * 1024) return 21;
689
690 if (!IS_ENABLED(CONFIG_PROFILE_ALL_BRANCHES) && size_is_constant)
691 BUILD_BUG_ON_MSG(1, "unexpected size in kmalloc_index()");
692 else
693 BUG();
694
695 /* Will never be reached. Needed because the compiler may complain */
696 return -1;
697 }
698 static_assert(PAGE_SHIFT <= 20);
699 #define kmalloc_index(s) __kmalloc_index(s, true)
700
701 #include <linux/alloc_tag.h>
702
703 /**
704 * kmem_cache_alloc - Allocate an object
705 * @cachep: The cache to allocate from.
706 * @flags: See kmalloc().
707 *
708 * Allocate an object from this cache.
709 * See kmem_cache_zalloc() for a shortcut of adding __GFP_ZERO to flags.
710 *
711 * Return: pointer to the new object or %NULL in case of error
712 */
713 void *kmem_cache_alloc_noprof(struct kmem_cache *cachep,
714 gfp_t flags) __assume_slab_alignment __malloc;
715 #define kmem_cache_alloc(...) alloc_hooks(kmem_cache_alloc_noprof(__VA_ARGS__))
716
717 void *kmem_cache_alloc_lru_noprof(struct kmem_cache *s, struct list_lru *lru,
718 gfp_t gfpflags) __assume_slab_alignment __malloc;
719 #define kmem_cache_alloc_lru(...) alloc_hooks(kmem_cache_alloc_lru_noprof(__VA_ARGS__))
720
721 /**
722 * kmem_cache_charge - memcg charge an already allocated slab memory
723 * @objp: address of the slab object to memcg charge
724 * @gfpflags: describe the allocation context
725 *
726 * kmem_cache_charge allows charging a slab object to the current memcg,
727 * primarily in cases where charging at allocation time might not be possible
728 * because the target memcg is not known (i.e. softirq context)
729 *
730 * The objp should be pointer returned by the slab allocator functions like
731 * kmalloc (with __GFP_ACCOUNT in flags) or kmem_cache_alloc. The memcg charge
732 * behavior can be controlled through gfpflags parameter, which affects how the
733 * necessary internal metadata can be allocated. Including __GFP_NOFAIL denotes
734 * that overcharging is requested instead of failure, but is not applied for the
735 * internal metadata allocation.
736 *
737 * There are several cases where it will return true even if the charging was
738 * not done:
739 * More specifically:
740 *
741 * 1. For !CONFIG_MEMCG or cgroup_disable=memory systems.
742 * 2. Already charged slab objects.
743 * 3. For slab objects from KMALLOC_NORMAL caches - allocated by kmalloc()
744 * without __GFP_ACCOUNT
745 * 4. Allocating internal metadata has failed
746 *
747 * Return: true if charge was successful otherwise false.
748 */
749 bool kmem_cache_charge(void *objp, gfp_t gfpflags);
750 void kmem_cache_free(struct kmem_cache *s, void *objp);
751
752 kmem_buckets *kmem_buckets_create(const char *name, slab_flags_t flags,
753 unsigned int useroffset, unsigned int usersize,
754 void (*ctor)(void *));
755
756 /*
757 * Bulk allocation and freeing operations. These are accelerated in an
758 * allocator specific way to avoid taking locks repeatedly or building
759 * metadata structures unnecessarily.
760 *
761 * Note that interrupts must be enabled when calling these functions.
762 */
763 void kmem_cache_free_bulk(struct kmem_cache *s, size_t size, void **p);
764
765 int kmem_cache_alloc_bulk_noprof(struct kmem_cache *s, gfp_t flags, size_t size, void **p);
766 #define kmem_cache_alloc_bulk(...) alloc_hooks(kmem_cache_alloc_bulk_noprof(__VA_ARGS__))
767
kfree_bulk(size_t size,void ** p)768 static __always_inline void kfree_bulk(size_t size, void **p)
769 {
770 kmem_cache_free_bulk(NULL, size, p);
771 }
772
773 void *kmem_cache_alloc_node_noprof(struct kmem_cache *s, gfp_t flags,
774 int node) __assume_slab_alignment __malloc;
775 #define kmem_cache_alloc_node(...) alloc_hooks(kmem_cache_alloc_node_noprof(__VA_ARGS__))
776
777 /*
778 * These macros allow declaring a kmem_buckets * parameter alongside size, which
779 * can be compiled out with CONFIG_SLAB_BUCKETS=n so that a large number of call
780 * sites don't have to pass NULL.
781 */
782 #ifdef CONFIG_SLAB_BUCKETS
783 #define DECL_BUCKET_PARAMS(_size, _b) size_t (_size), kmem_buckets *(_b)
784 #define PASS_BUCKET_PARAMS(_size, _b) (_size), (_b)
785 #define PASS_BUCKET_PARAM(_b) (_b)
786 #else
787 #define DECL_BUCKET_PARAMS(_size, _b) size_t (_size)
788 #define PASS_BUCKET_PARAMS(_size, _b) (_size)
789 #define PASS_BUCKET_PARAM(_b) NULL
790 #endif
791
792 /*
793 * The following functions are not to be used directly and are intended only
794 * for internal use from kmalloc() and kmalloc_node()
795 * with the exception of kunit tests
796 */
797
798 void *__kmalloc_noprof(size_t size, gfp_t flags)
799 __assume_kmalloc_alignment __alloc_size(1);
800
801 void *__kmalloc_node_noprof(DECL_BUCKET_PARAMS(size, b), gfp_t flags, int node)
802 __assume_kmalloc_alignment __alloc_size(1);
803
804 void *__kmalloc_cache_noprof(struct kmem_cache *s, gfp_t flags, size_t size)
805 __assume_kmalloc_alignment __alloc_size(3);
806
807 void *__kmalloc_cache_node_noprof(struct kmem_cache *s, gfp_t gfpflags,
808 int node, size_t size)
809 __assume_kmalloc_alignment __alloc_size(4);
810
811 void *__kmalloc_large_noprof(size_t size, gfp_t flags)
812 __assume_page_alignment __alloc_size(1);
813
814 void *__kmalloc_large_node_noprof(size_t size, gfp_t flags, int node)
815 __assume_page_alignment __alloc_size(1);
816
817 /**
818 * kmalloc - allocate kernel memory
819 * @size: how many bytes of memory are required.
820 * @flags: describe the allocation context
821 *
822 * kmalloc is the normal method of allocating memory
823 * for objects smaller than page size in the kernel.
824 *
825 * The allocated object address is aligned to at least ARCH_KMALLOC_MINALIGN
826 * bytes. For @size of power of two bytes, the alignment is also guaranteed
827 * to be at least to the size. For other sizes, the alignment is guaranteed to
828 * be at least the largest power-of-two divisor of @size.
829 *
830 * The @flags argument may be one of the GFP flags defined at
831 * include/linux/gfp_types.h and described at
832 * :ref:`Documentation/core-api/mm-api.rst <mm-api-gfp-flags>`
833 *
834 * The recommended usage of the @flags is described at
835 * :ref:`Documentation/core-api/memory-allocation.rst <memory_allocation>`
836 *
837 * Below is a brief outline of the most useful GFP flags
838 *
839 * %GFP_KERNEL
840 * Allocate normal kernel ram. May sleep.
841 *
842 * %GFP_NOWAIT
843 * Allocation will not sleep.
844 *
845 * %GFP_ATOMIC
846 * Allocation will not sleep. May use emergency pools.
847 *
848 * Also it is possible to set different flags by OR'ing
849 * in one or more of the following additional @flags:
850 *
851 * %__GFP_ZERO
852 * Zero the allocated memory before returning. Also see kzalloc().
853 *
854 * %__GFP_HIGH
855 * This allocation has high priority and may use emergency pools.
856 *
857 * %__GFP_NOFAIL
858 * Indicate that this allocation is in no way allowed to fail
859 * (think twice before using).
860 *
861 * %__GFP_NORETRY
862 * If memory is not immediately available,
863 * then give up at once.
864 *
865 * %__GFP_NOWARN
866 * If allocation fails, don't issue any warnings.
867 *
868 * %__GFP_RETRY_MAYFAIL
869 * Try really hard to succeed the allocation but fail
870 * eventually.
871 */
kmalloc_noprof(size_t size,gfp_t flags)872 static __always_inline __alloc_size(1) void *kmalloc_noprof(size_t size, gfp_t flags)
873 {
874 if (__builtin_constant_p(size) && size) {
875 unsigned int index;
876
877 if (size > KMALLOC_MAX_CACHE_SIZE)
878 return __kmalloc_large_noprof(size, flags);
879
880 index = kmalloc_index(size);
881 return __kmalloc_cache_noprof(
882 kmalloc_caches[kmalloc_type(flags, _RET_IP_)][index],
883 flags, size);
884 }
885 return __kmalloc_noprof(size, flags);
886 }
887 #define kmalloc(...) alloc_hooks(kmalloc_noprof(__VA_ARGS__))
888
889 #define kmem_buckets_alloc(_b, _size, _flags) \
890 alloc_hooks(__kmalloc_node_noprof(PASS_BUCKET_PARAMS(_size, _b), _flags, NUMA_NO_NODE))
891
892 #define kmem_buckets_alloc_track_caller(_b, _size, _flags) \
893 alloc_hooks(__kmalloc_node_track_caller_noprof(PASS_BUCKET_PARAMS(_size, _b), _flags, NUMA_NO_NODE, _RET_IP_))
894
kmalloc_node_noprof(size_t size,gfp_t flags,int node)895 static __always_inline __alloc_size(1) void *kmalloc_node_noprof(size_t size, gfp_t flags, int node)
896 {
897 if (__builtin_constant_p(size) && size) {
898 unsigned int index;
899
900 if (size > KMALLOC_MAX_CACHE_SIZE)
901 return __kmalloc_large_node_noprof(size, flags, node);
902
903 index = kmalloc_index(size);
904 return __kmalloc_cache_node_noprof(
905 kmalloc_caches[kmalloc_type(flags, _RET_IP_)][index],
906 flags, node, size);
907 }
908 return __kmalloc_node_noprof(PASS_BUCKET_PARAMS(size, NULL), flags, node);
909 }
910 #define kmalloc_node(...) alloc_hooks(kmalloc_node_noprof(__VA_ARGS__))
911
912 /**
913 * kmalloc_array - allocate memory for an array.
914 * @n: number of elements.
915 * @size: element size.
916 * @flags: the type of memory to allocate (see kmalloc).
917 */
kmalloc_array_noprof(size_t n,size_t size,gfp_t flags)918 static inline __alloc_size(1, 2) void *kmalloc_array_noprof(size_t n, size_t size, gfp_t flags)
919 {
920 size_t bytes;
921
922 if (unlikely(check_mul_overflow(n, size, &bytes)))
923 return NULL;
924 if (__builtin_constant_p(n) && __builtin_constant_p(size))
925 return kmalloc_noprof(bytes, flags);
926 return kmalloc_noprof(bytes, flags);
927 }
928 #define kmalloc_array(...) alloc_hooks(kmalloc_array_noprof(__VA_ARGS__))
929
930 /**
931 * krealloc_array - reallocate memory for an array.
932 * @p: pointer to the memory chunk to reallocate
933 * @new_n: new number of elements to alloc
934 * @new_size: new size of a single member of the array
935 * @flags: the type of memory to allocate (see kmalloc)
936 *
937 * If __GFP_ZERO logic is requested, callers must ensure that, starting with the
938 * initial memory allocation, every subsequent call to this API for the same
939 * memory allocation is flagged with __GFP_ZERO. Otherwise, it is possible that
940 * __GFP_ZERO is not fully honored by this API.
941 *
942 * See krealloc_noprof() for further details.
943 *
944 * In any case, the contents of the object pointed to are preserved up to the
945 * lesser of the new and old sizes.
946 */
krealloc_array_noprof(void * p,size_t new_n,size_t new_size,gfp_t flags)947 static inline __realloc_size(2, 3) void * __must_check krealloc_array_noprof(void *p,
948 size_t new_n,
949 size_t new_size,
950 gfp_t flags)
951 {
952 size_t bytes;
953
954 if (unlikely(check_mul_overflow(new_n, new_size, &bytes)))
955 return NULL;
956
957 return krealloc_noprof(p, bytes, flags);
958 }
959 #define krealloc_array(...) alloc_hooks(krealloc_array_noprof(__VA_ARGS__))
960
961 /**
962 * kcalloc - allocate memory for an array. The memory is set to zero.
963 * @n: number of elements.
964 * @size: element size.
965 * @flags: the type of memory to allocate (see kmalloc).
966 */
967 #define kcalloc(n, size, flags) kmalloc_array(n, size, (flags) | __GFP_ZERO)
968
969 void *__kmalloc_node_track_caller_noprof(DECL_BUCKET_PARAMS(size, b), gfp_t flags, int node,
970 unsigned long caller) __alloc_size(1);
971 #define kmalloc_node_track_caller_noprof(size, flags, node, caller) \
972 __kmalloc_node_track_caller_noprof(PASS_BUCKET_PARAMS(size, NULL), flags, node, caller)
973 #define kmalloc_node_track_caller(...) \
974 alloc_hooks(kmalloc_node_track_caller_noprof(__VA_ARGS__, _RET_IP_))
975
976 /*
977 * kmalloc_track_caller is a special version of kmalloc that records the
978 * calling function of the routine calling it for slab leak tracking instead
979 * of just the calling function (confusing, eh?).
980 * It's useful when the call to kmalloc comes from a widely-used standard
981 * allocator where we care about the real place the memory allocation
982 * request comes from.
983 */
984 #define kmalloc_track_caller(...) kmalloc_node_track_caller(__VA_ARGS__, NUMA_NO_NODE)
985
986 #define kmalloc_track_caller_noprof(...) \
987 kmalloc_node_track_caller_noprof(__VA_ARGS__, NUMA_NO_NODE, _RET_IP_)
988
kmalloc_array_node_noprof(size_t n,size_t size,gfp_t flags,int node)989 static inline __alloc_size(1, 2) void *kmalloc_array_node_noprof(size_t n, size_t size, gfp_t flags,
990 int node)
991 {
992 size_t bytes;
993
994 if (unlikely(check_mul_overflow(n, size, &bytes)))
995 return NULL;
996 if (__builtin_constant_p(n) && __builtin_constant_p(size))
997 return kmalloc_node_noprof(bytes, flags, node);
998 return __kmalloc_node_noprof(PASS_BUCKET_PARAMS(bytes, NULL), flags, node);
999 }
1000 #define kmalloc_array_node(...) alloc_hooks(kmalloc_array_node_noprof(__VA_ARGS__))
1001
1002 #define kcalloc_node(_n, _size, _flags, _node) \
1003 kmalloc_array_node(_n, _size, (_flags) | __GFP_ZERO, _node)
1004
1005 /*
1006 * Shortcuts
1007 */
1008 #define kmem_cache_zalloc(_k, _flags) kmem_cache_alloc(_k, (_flags)|__GFP_ZERO)
1009
1010 /**
1011 * kzalloc - allocate memory. The memory is set to zero.
1012 * @size: how many bytes of memory are required.
1013 * @flags: the type of memory to allocate (see kmalloc).
1014 */
kzalloc_noprof(size_t size,gfp_t flags)1015 static inline __alloc_size(1) void *kzalloc_noprof(size_t size, gfp_t flags)
1016 {
1017 return kmalloc_noprof(size, flags | __GFP_ZERO);
1018 }
1019 #define kzalloc(...) alloc_hooks(kzalloc_noprof(__VA_ARGS__))
1020 #define kzalloc_node(_size, _flags, _node) kmalloc_node(_size, (_flags)|__GFP_ZERO, _node)
1021
1022 void *__kvmalloc_node_noprof(DECL_BUCKET_PARAMS(size, b), gfp_t flags, int node) __alloc_size(1);
1023 #define kvmalloc_node_noprof(size, flags, node) \
1024 __kvmalloc_node_noprof(PASS_BUCKET_PARAMS(size, NULL), flags, node)
1025 #define kvmalloc_node(...) alloc_hooks(kvmalloc_node_noprof(__VA_ARGS__))
1026
1027 #define kvmalloc(_size, _flags) kvmalloc_node(_size, _flags, NUMA_NO_NODE)
1028 #define kvmalloc_noprof(_size, _flags) kvmalloc_node_noprof(_size, _flags, NUMA_NO_NODE)
1029 #define kvzalloc(_size, _flags) kvmalloc(_size, (_flags)|__GFP_ZERO)
1030
1031 #define kvzalloc_node(_size, _flags, _node) kvmalloc_node(_size, (_flags)|__GFP_ZERO, _node)
1032 #define kmem_buckets_valloc(_b, _size, _flags) \
1033 alloc_hooks(__kvmalloc_node_noprof(PASS_BUCKET_PARAMS(_size, _b), _flags, NUMA_NO_NODE))
1034
1035 static inline __alloc_size(1, 2) void *
kvmalloc_array_node_noprof(size_t n,size_t size,gfp_t flags,int node)1036 kvmalloc_array_node_noprof(size_t n, size_t size, gfp_t flags, int node)
1037 {
1038 size_t bytes;
1039
1040 if (unlikely(check_mul_overflow(n, size, &bytes)))
1041 return NULL;
1042
1043 return kvmalloc_node_noprof(bytes, flags, node);
1044 }
1045
1046 #define kvmalloc_array_noprof(...) kvmalloc_array_node_noprof(__VA_ARGS__, NUMA_NO_NODE)
1047 #define kvcalloc_node_noprof(_n,_s,_f,_node) kvmalloc_array_node_noprof(_n,_s,(_f)|__GFP_ZERO,_node)
1048 #define kvcalloc_noprof(...) kvcalloc_node_noprof(__VA_ARGS__, NUMA_NO_NODE)
1049
1050 #define kvmalloc_array(...) alloc_hooks(kvmalloc_array_noprof(__VA_ARGS__))
1051 #define kvcalloc_node(...) alloc_hooks(kvcalloc_node_noprof(__VA_ARGS__))
1052 #define kvcalloc(...) alloc_hooks(kvcalloc_noprof(__VA_ARGS__))
1053
1054 void *kvrealloc_noprof(const void *p, size_t size, gfp_t flags)
1055 __realloc_size(2);
1056 #define kvrealloc(...) alloc_hooks(kvrealloc_noprof(__VA_ARGS__))
1057
1058 extern void kvfree(const void *addr);
1059 DEFINE_FREE(kvfree, void *, if (!IS_ERR_OR_NULL(_T)) kvfree(_T))
1060
1061 extern void kvfree_sensitive(const void *addr, size_t len);
1062
1063 unsigned int kmem_cache_size(struct kmem_cache *s);
1064
1065 /**
1066 * kmalloc_size_roundup - Report allocation bucket size for the given size
1067 *
1068 * @size: Number of bytes to round up from.
1069 *
1070 * This returns the number of bytes that would be available in a kmalloc()
1071 * allocation of @size bytes. For example, a 126 byte request would be
1072 * rounded up to the next sized kmalloc bucket, 128 bytes. (This is strictly
1073 * for the general-purpose kmalloc()-based allocations, and is not for the
1074 * pre-sized kmem_cache_alloc()-based allocations.)
1075 *
1076 * Use this to kmalloc() the full bucket size ahead of time instead of using
1077 * ksize() to query the size after an allocation.
1078 */
1079 size_t kmalloc_size_roundup(size_t size);
1080
1081 void __init kmem_cache_init_late(void);
1082
1083 #endif /* _LINUX_SLAB_H */
1084